Low-molecular and high-molecular weight emulsifiers, particularly based on polyisobutylene, and mixtures thereof

ABSTRACT

Low molecular weight and high molecular weight two-block emulsifiers, in particular based on polyisobutylene, of the formula (Ia) or (Ib) and mixtures thereof  
                 
 
     where L a  is a polyisobutylenyl group having a number average molecular weight M n  of from 300 to 1 000 and L b  is a polyisobutylenyl group having a number average molecular weight M n  of from 2 000 to 20 000,  
     -A- is —O—, —N(H) or —N(R 1 )—,  
     M +  is H +  or an alkali metal ion, 0.5 alkaline earth metal ion or NH 4   + , where one or more H in NH 4   +  may be replaced by alkyl,  
     R is a linear or branched saturated hydrocarbon radical which carries at least one substituent selected from the group consisting of OH, NH 2  and NH 3   +  and, if required, one or more C(O)H groups and, if required, contains one or more nonneighboring —O— and/or secondary amines and/or tertiary amines, where one or more H in the NH 2 — or NH 3   +  groups may be replaced by alkyl, and  
     R 1  is a linear or branched saturated hydrocarbon radical which, if required, carries one or more substituents selected from the group consisting of OH, NH 2 , NH 3   +  and C(O)H and, if required, contains one or more nonneighboring —O— and/or secondary amines and/or tertiary amines, and where one or more H in the NH 2 — or NH 3   +  groups may be replaced by alkyl, and  
     the proportion of A-R in the compound of the formula (Ia) or (Ib) is at least 20% by weight,  
     are described.

[0001] The present invention relates to low molecular weight and highmolecular weight compounds, in particular based on polyisobutylene, andmixtures thereof, which are suitable as emulsifiers for water-in-oilemulsions, processes for the preparation of such compounds and theemulsions themselves.

[0002] The present invention also relates to the use of such compoundsas additives for fuels and lubricants and as corrosion-inhibitingadditives in water-containing liquids, and fuels, lubricants, fuel andlubricant additive concentrates and water-containing liquids containingthe novel compounds.

[0003] The prior art discloses various types of compounds havingemulsifying properties. Inter alia, derivatives of succinic anhydridesubstituted by a polyisobutylenyl group are used in variousapplications.

[0004] Thus, for example U.S. Pat. No. 4,225,447 describes water-in-oilemulsions which are used as lubricants and contain a succinic anhydridesubstituted by an alkylenyl group (such as a polyisobutylenyl group),preferably having a number average molecular weight M_(n) of from 300 to3 000 g/mol, an alkali metal or alkaline earth metal salt of a succinicacid substituted by an alkenyl group or a succinamide substituted by analkenyl group, as an emulsifier, if required in combination with thesalt of a resin acid.

[0005] EP-A 0 156 572 describes the use of surface-active substancesbased on succinic acid derivatives substituted by polyisobutylenylgroups, preferably having a number average molecular weight M_(n) offrom 400 to 5 000, and having an anionic group for the preparation ofwater-in-oil or oil-in-water emulsions. Suitable anionic groups arephosphate, phosphonate, sulfate, sulfonate and carboxymethyl groups.

[0006] The Applicant's German application filed on Jan. 25, 2000 andhaving the application number 100 03 105.6 describes the use ofalkoxylated polyisobutylenes as emulsifiers in water-in-fuel emulsions.These alkoxylated polyisobutylenes can be described by the formulaR—(CH₂)_(n)—(O-A)_(m)—OH. Here, R is a polyisobutylene having a weightaverage molar mass of from 300 to 2 300, preferably from 500 to 2 000. Ais an alkylene radical of 2 to 8 carbon atoms. m is a number from 1 to200 which is chosen so that the alkoxylated polyisobutylene containsfrom 0.2 to 1.5 alkylene oxide units per C₄ unit, preferably 0.5alkylene oxide unit per C₄ unit; n is either 0 or 1.

[0007] The Applicant's German application filed on Jul. 28, 2000 andhaving the application number 100 36 956.1 describes, inter alia, theuse of amides of the formula R¹R²NR³ as emulsifiers in water-in-oilemulsions, where R³ is an acyl radical of a mono- or polycarboxylicacid, and R¹ may be derived, inter alia, from a poly-1-butylene,poly-2-butylene or poly-isobutylene or mixtures thereof and R² may be apolyalkylenepolyamine radical or a polyalkyleneimine radical.

[0008] WO 00/15740 discloses water-in-fuel emulsions which contain, asemulsifiers, two succinic acid derivatives linked via a linker such asalkanolamine, polyamine or polyol and substituted by hydrocarbonradicals, such as polyisobutylenyl groups, in one embodiment onesuccinic acid derivative containing a polyisobutylenyl group of 8 to 25carbon atoms and the other sucinnic acid derivative containing apolyisobutylenyl group of 50 to 400 carbon atoms.

[0009] GB-A 2,157,744 discloses drilling fluids which contain both graftor block copolymers of polycarboxylic acids and polyethylene glycol andcompounds which are prepared from a succinic anhydride substituted by apolyisobutylenyl group and preferably having a number average molecularweight M_(n) of from 400 to 5 000, and polyols, preferably polyamines,hydroxycarboxylic acids or amino alcohols.

[0010] U.S. Pat. No. 4,708,753 discloses water-in-fuel emulsions whichcontain, inter alia, mono- or disalts of succinic acid with amines oramine salts of succinic monoesters as emulsifiers. These salts form byreaction of alkanolamines, polyamines, oligoalcohols or polyols withsuccinic anhydrides which are substituted by C₂₀-C₅₀₀-hydrocarbonradicals, such as polyisobutyenyl groups. In the examples, only thosesalts of succinic acids or of their monoesters are described which carrya polyisobutylenyl group having a number average molecular weight of 950to 1 700.

[0011] Friction-reducing additives for fuels and lubricants as well asemulsifiers are disclosed in the prior art.

[0012] Thus, U.S. Pat. No. 5,858,029 describes friction-reducingadditives for fuels and lubricants, in particular compounds of theformula R¹—(OR²—)_(a)NH(CO)—R³—OH being used as friction-reducingadditives, where R¹ is C₁- to C₆₀-alkyl, R² is C₁- to C₄-alkylene, a isan integer from 1 to 12 and R³ is C₁- to C₄-alkylene or substitutedalkylene or cycloalkylene. In addition, succinimides substituted bypolyisobutylenyl groups may be contained as dispersants andpolyalkyleneamines, such as polyisobutyleneamines, as surfactants.

[0013] The abovementioned compounds disclosed in the prior art havevarious disadvantages with regard to preparation and/or productproperties. In the case of some compounds, byproducts are obtained inthe synthesis in various yields and—unless they are removed—can make itdifficult to establish a constant viscosity of the emulsifier.Disadvantages may also arise in the preparation of the emulsions:frequently, the emulsions have insufficient stability, so that phaseseparation occurs during storage. The emulsifiers used therefore have tobe employed in high concentrations in order to permit the formation of astable emulsion.

[0014] There is therefore a need for compounds which can be used asemulsifiers and which do not have the stated disadvantages. Particularlyin the area of water-in-fuel emulsions, emulsifiers which producerelatively stable emulsions and additionally permit as far as possiblecomplete and substantially residue-free combustion of the fuel arerequired.

[0015] It is an object of the present invention to provide furthercompounds which can be used as emulsifiers in water-in-oil emulsions.

[0016] We have found that this object is achieved by compounds of theformulae (Ia) and (Ib)

[0017] where L^(a) is a polyisobutylenyl group having a number averagemolecular weight M_(n) of from 300 to 1 000,

[0018] L^(b) is a polyisobutylenyl group having a number averagemolecular weight M_(n) of from 2 000 to 20 000,

[0019] -A- is —O—, —N(H)— or —N(R¹)—,

[0020] M⁺ is H⁺ or an alkali metal ion, 0.5 alkaline earth metal ion orNH₄ ⁺, where one or more H in NH₄ ⁺ may be replaced by alkyl,

[0021] R is a linear or branched saturated hydrocarbon radical whichcarries at least one substituent selected from the group consisting ofOH, NH₂ and NH₃ ⁺ and, if required, one or more C(O)H groups and, ifrequired, contains one or more nonneighboring —O— and/or secondaryamines and/or tertiary amines, where one or more H in the NH₂— or NH₃ ⁺groups may be replaced by alkyl, and

[0022] R¹ is a linear or branched saturated hydrocarbon radical which,if required, carries one or more substituents selected from the groupconsisting of OH, NH₂, NH₃ ⁺ and C(O)H and, if required, contains one ormore nonneighboring —O— and/or secondary amines and/or tertiary amines,and where one or more H in the NH₂— or NH₃ ⁺ groups may be replaced byalkyl, and

[0023] the proportion of A-R in the compound of the formula (Ia) or (Ib)is at least 20% by weight.

[0024] Compounds of the formula (Ia) in which the proportion of thehydrophilic radical A-R has low values, such as from 5.2 to 15.2% byweight, are known per se and are described in GB-A 2,157,744 and U.S.Pat. No. 4,708,753. However, the advantageous properties as anemulsifier, which occur in the case of the novel compounds having an A-Rproportion of ≧20% by weight, are not recognized therein.

[0025] The novel compounds can be used both individually and in the formof a mixture as emulsifiers in water-in-oil emulsions. It is possible toproduce emulsions which are more stable than with the use ofconventional emulsifiers.

[0026] In particular, the compounds of the formula (Ib) can beconsidered as two-block emulsifiers linked via a linker, the lipophilicblock L^(a) or L^(b) being linked to the linker succinic acid by acovalent C—C bond and the hydrophilic block R or R¹ being linked to saidlinker via an ester or amide bond.

[0027] Preferred compounds of the formula (Ia) are those in which

[0028] L^(a) is a polyisobutylenyl group having a number averagemolecular weight M_(n) of from 350 to 950, in particular from 350 to650, and/or

[0029] L^(a) is a polyisobutylenyl group which has a polydispersity of≦3.0, preferably from 1.1 to 2.5, particularly preferably from 1.1 to2.0, and/or

[0030] the proportion of A-R in the compound of the formula (Ia) is atleast 25, in particular from 35 to 60, % by weight, and/or

[0031] R is composed of [—CH₂—CH₂—X], [—CH(CH₃)—CH₂—X] and/or[—CH₂—CH(CH₃)—X] units, where X is O or NH.

[0032] Preferred compounds of the formula (Ib) are those in which

[0033] L^(b) is a polyisobutylenyl group having a number averagemolecular weight of from 2 000 to 12 000, in particular from 2 300 to 5000, and/or

[0034] L^(b) is a polyisobutylenyl group which has a polydispersity of≦3.0, preferably from 1.1 to 2.5, particularly preferably from 1.1 to2.0, and/or

[0035] the proportion of A-R in the compound of the formula (Ib) is atleast 25, in particular from 35 to 60, % by weight, and/or

[0036] R is composed of [—CH₂—CH₂—X], [—CH(CH₃)—CH₂—X] and/or[—CH₂—CH(CH₃)—X] units, where X is O or NH.

[0037] Particularly preferred compounds of the formula (Ia) or (Ib) arethose in which A is —O— and R is a monovalent radical of an oligomer orpolymer of ethylene oxide and/or propylene oxide or a monovalent radicalof a block copolymer of ethylene oxide and propylene oxide.

[0038] Particularly effective emulsifiers are compounds of the formula(Ia) in which L^(a) is a polyisobutylenyl group having a number averagemolecular weight M_(n) of from 350 to 950, in particular from 350 to650, this polyisobutylenyl group having, if required, a polydispersityof ≦3.0, preferably from 1.1 to 2.5, particularly preferably from 1.1 to2.0. It has been found that the total amount of emulsifier for thepreparation of stable emulsions can be reduced if

[0039] the emulsifier used is a mixture containing

[0040] (a) not more than 99, preferably from 98 to 80, particularlypreferably from 97 to 85, % by weight of at least one compound of theformula (Ia),

[0041] (b) at least 1, preferably from 2 to 20, particularly preferablyfrom 3 to 15, % by weight of at least one compound of the formula (Ib),

[0042] where L^(a) is a polyisobutylenyl group having a number averagemolecular weight M_(n) of from 300 to 1 000 and L^(b) is apolyisobutylenyl group having a number average molecular weight M_(n) offrom 2 000 to 20 000,

[0043] -A- is —O—, —N(H) or —N(R¹)—,

[0044] M⁺ is H⁺, an alkali metal ion, 0.5 alkaline earth metal ion orNH₄ ⁺, where one or more H in NH₄ ⁺ may be replaced by alkyl,

[0045] R is a linear or branched saturated hydrocarbon radical whichcarries at least one substituent selected from the group consisting ofOH, NH₂ and NH₃ ⁺ and, if required, one or more C(O)H groups and, ifrequired, contains one or more nonneighboring —O— and/or secondaryamines and/or tertiary amines, and where one or more H in the NH₂— orNH₃ ⁺ groups may be replaced by alkyl, and

[0046] R¹ is a linear or branched saturated hydrocarbon radical which,if required, carries one or more substituents selected from the groupconsisting of OH, NH₂, NH₃ ⁺ and C(O)H and, if required, contains one ormore nonneighboring —O— and/or secondary amines and/or tertiary amines,and where one or more H in the NH₂— or NH₃ ⁺ groups may be replaced byalkyl, and

[0047] the proportion of A-R in the compound of the formula (Ia) is atleast 10% by weight and that in the compound of the formula (Ib) is atleast 20% by weight.

[0048] Effective emulsifier mixtures are obtained not only with the useof compounds of the formula (Ia) having hydrophilic moieties of at least20% by weight but also with the use of compounds of the formula (Ia)having hydrophilic moieties of at least 10% by weight.

[0049] Preferred novel mixtures are those which—in addition to at leastone compound of the formula (Ib)—

[0050] contain not more than 99, preferably from 98 to 80, particularlypreferably from 97 to 85, % by weight of at least one compound of theformula (Ia), where L^(a) is a polyisobutylenyl group having a numberaverage molecular weight M_(n) of from 350 to 950, in particular from350 to 650, and/or the proportion of A-R in the compound of the formula(Ia) is at least 15, preferably at least 20, particularly preferably atleast 25, very particularly preferably from 35 to 60, % by weight.

[0051] Other preferred novel mixtures are those which—in addition to atleast one compound of the formula (Ia)—

[0052] contain at least 1, preferably from 2 to 20, particularlypreferably from 3 to 15, % by weight of at least one compound of theformula (Ib), where L^(b) is a polyisobutylenyl group having a numberaverage molecular weight M_(n) of from 2 000 to 12 000, in particularfrom 2 300 to 5 000, and/or the proportion of A-R in the compound of theformula (Ib) is at least 25, in particular from 35 to 60, % by weight.

[0053] The present invention also relates to processes for thepreparation of compounds of the formula (Ia) or (Ib). Here,polyisobutylene is reacted with fumaryl dichloride, fumaric acid, maleyldichloride, maleic anhydride or maleic acid, preferably with maleicanhydride or maleyl dichloride, particularly preferably with maleicanhydride, to give succinic acid derivatives of the formula (IIa), (IIb)or (IIc), where L^(a) is a polyisobutylenyl group having a numberaverage molecular weight M_(n) of from 300 to 1 000 and L^(b) is apolyisobutylenyl group having a number average molecular weight M_(n) offrom 2 000 to 20 000.

[0054] The reaction is carried out by the processes known to a personskilled in the art and, for example, analogously to the processes,described in DE-A 195 19 042, DE-A 43 19 671 and DE-A 43 19 672, for thereaction of polyisobutylenes with maleic anhydride.

[0055] The number average molecular weight M_(n) of the resultingsuccinic anhydride derivative—substituted by a polyisobutylenylgroup—can be characterized by means of the saponification number [mgKOH/g of substance].

[0056] The substituted succinic acid derivatives of the formulae (IIa)and (IIb) are then reacted by the process known to a person skilled inthe art, with polar reactants ROH or RR¹NH, where R is a linear orbranched saturated hydrocarbon radical which carries at least onesubstituent selected from the group consisting of OH, NH₂ and NH₃ ⁺ and,if required, one or more C(O)H groups and, if required, contains one ormore nonneighboring —O— and/or secondary amines and/or tertiary amines,and where one or more H in the NH₂— or NH₃ ⁺ groups may be replaced byalkyl, and

[0057] R¹ is a linear or branched saturated hydrocarbon radical which,if required, carries one or more substituents selected from the groupconsisting of OH, NH₂, NH₃ ⁺ and C(O)H and, if required, contains one ormore nonneighboring —O— and/or secondary amines and/or tertiary amines,and where one or more H in the NH₂— or NH₃ ⁺ groups may be replaced byalkyl.

[0058] The alkyl radicals which may replace the H atoms may beC₁-C₄-alkyl.

[0059] Examples of suitable polar reactants ROH and RR¹NH arealkanolamines, polyamines, oligoalcohols, polyols, oligoalkyleneglycols, polyalkylene glycols and carbohydrates and sugars. Other polarreactants may be ethylene oxide and/or propylene oxide. The reactionwith polyethylene glycol, polypropylene glycol, (block) copolymersthereof, ethylene oxide or propylene oxide is preferred. For thepreparation of low molecular weight compounds of the formula (Ia), thereaction with alkanolamines, such as di- or triethanolamine,tris(hydroxymethyl)aminomethane and salts thereof, oligoalcohols, suchas sorbitol and pentaerythritol, or carbohydrates and sugars is alsopreferred. The reaction with tris(hydroxymethyl)aminomethane, choline,sugars and polyethylene glycol is particularly preferred for thepreparation of compounds of the formula (Ia).

[0060] The amount of the polar reactant is chosen so that the proportionof the hydrophilic radical A-R in the compound of the formula (Ia) or(Ib) is at least 20, preferably 25, particularly preferably from 35 to60, % by weight. Compounds of the formula (Ia) in which the hydrophilicmoiety comprises from 10 to 20% by weight can also be prepared by theprocesses described. The ratio of the substituted succinic acidderivatives (IIa), (IIb) or (IIc) to the alkanolamines, polyamines,oligoalcohols, polyols, oligoalkylene glycols or polyalkylene glycols inthe reaction is in general from 1:(0.75 to 2), preferably from 1:(0.8 to1.2), particularly preferably 1:1. In the reaction of ethylene oxideand/or propylene oxide, the amount of ethylene oxide and/or propyleneoxide is chosen according to the desired chain length of the hydrophilicradical A-R.

[0061] Compounds of the formula (Ia) or (Ib) where A is —O— and R is amonovalent radical of an oligomer or polymer of ethylene oxide and/orpropylene oxide or a monovalent radical of a block copolymer of ethyleneoxide and propylene oxide can be obtained both by reacting polyethyleneglycol, polypropylene glycol or (block) copolymers thereof with thesubstituted succinic acid derivatives (IIa), (IIb) or (IIc) and byreacting ethylene oxide and/or propylene oxide with the substitutedsuccinic acid derivatives (IIa), (IIb) or (IIc).

[0062] By reacting the substituted succinic acid derivatives (IIa),(IIb) or (IIc) with said polar reactants, succinic monoesters orsuccinic monoamides are obtained. When alkanolamines are used, thehydroxyl and/or amino groups react so that in general mixtures ofsuccinic monoesters and succinic monoamides are obtained. If maleyl orfumaryl dichloride is used as a starting material, the C(O)Cl groupstill present after said reaction steps is hydrolyzed to the CO₂H group.The free CO₂H group present in the succinic monoesters and succinicmonoamides can then be reacted with NH₃, amines or alkali metal oralkaline earth metal salts to give the corresponding amine, alkali metalor alkaline earth metal salts. These salts are compounds of the formula(Ia) or (Ib) where M⁺ is an alkali metal ion, 0.5 alkaline earth metalion or NH₄ ⁺, it being possible for one or more H in NH₄ ⁺ to bereplaced by alkyl. Suitable amines for the salt formation are primary,secondary and tertiary amines which carry linear C₁-C₄-alkyl or branchedC₃-C₆-alkyl groups. These alkyl groups may also be substituted by one ormore hydroxyl groups. Examples of suitable alkylamines are diethylamine,diisopropylamine, trimethylamine, mono-, di- and triethanolamine andtris(hydroxymethyl)aminomethane.

[0063] In general, polyisobutylenes having a number average molecularweight M_(n) of from 300 to 1 000, preferably from 350 to 950,particularly preferably from 350 to 650, are used for the preparation ofthe compounds of the formula (Ia).

[0064] In general, polyisobutylenes having a number average molecularweight M_(n) of from 2 000 to 20 000, preferably from 2000 to 12 000,particularly preferably from 2 300 to 5 000, are used for thepreparation of the compounds of the formula (Ib).

[0065] Among the polyisobutylenes having a number average molecularweight M_(n) in said ranges, those which have a high content ofvinylidene groups are preferably used. In the context of the presentinvention, this is understood as meaning ≧70, preferably ≧80,particularly preferably ≧85, mol % of vinylidene groups.

[0066] Particularly preferably used polyisobutylenes are those whichhave a number average molecular weight M_(n) in the abovementionedranges, a high content of vinylidene groups and a uniform polymerskeleton structure. In the context of the present invention, these areunderstood as meaning polyisobutylenes which are composed of at least80, preferably at least 90, particularly preferably at least 95, % byweight of isobutylene units.

[0067] Polyisobutylenes having a number average molecular weight M_(n)in said ranges, a high content of vinylidene groups, a uniform skeletonstructure and a polydispersity of ≦3.0, preferably from 1.1 to 2.5,particularly preferably from 1.1 to 20.0 are very particularlypreferred. Polydispersity is understood as meaning the quotientM_(w)/M_(n) of weight average molecular weight M_(w) and number averagemolecular weight M_(n).

[0068] Polyisobutylenes which have a number average molecular weightM_(n) in said ranges, are composed substantially of isobutylene unitsand have a high content of vinylidene groups are available, for example,under the trade name Glissopal® from BASF AG, such as Glissopal® 1000having an M_(n) of 1 000, Glissopal® V 33 having an M_(n) of 550 andGlissopal® 2300 having an M_(n) of 2 300.

[0069] Examples of suitable alkanolamines, polyamines, oligoalcohols,polyols and polyalkylene glycols which may be used for the preparationof the novel compounds are described in WO 00/15740.

[0070] Examples of alkanolamines are monoethanolamine, diethanolamine,2-amino-1-butanol, 2-amino-2-methyl-1-propanol,2-amino-2-methyl-1,3-propanediol, 2-amino-2-ethyl-1,3-propanediol,N-(2-hydroxypropyl)-N′-(2-aminoethyl)piperazine,tris(hydroxymethyl)-amino-methane, 2-amino-1-butanol,β-(2-hydroxyethoxy)ethylamine, glucamine, glucosamine,4-amino-3-hydroxy-3-methyl-1-butene,N-(3-aminopropyl)-4-(2-hydroxy-ethyl)piperidine,2-amino-6-methyl-6-heptanol, 5-amino-1-pentanol,N-(2-hydroxyethyl)-1,3-diaminopropane, 1,3-diamino-2-hydroxypropane,N-(2-hydroxyethyl)ethylenediamine,N,N-bis(2-hydroxy-ethyl)ethylenediamine,N-(2-hydroxyethoxyethyl)ethylenediamine, 1-(2-hydroxy-ethyl)piperazine,monohydroxypropyl-substituted diethylenetriamine,dihydroxypropyl-substituted tetraethylenepentamine andN-(3-hydroxybutyl)-tetra-methylen-diamine.

[0071] The salts of said alkanolamines may also be used. In these salts,one or more of the H atoms bonded to N atoms may be replaced by linearC₁-C₆-alkyl or branched C₃-C₆-alkyl groups. Choline may be mentioned byway of example.

[0072] Examples of suitable polyamines are polyalkylenepolyamines, suchas polymethylenepolyamines, polyethylenepolyamines,polypropylenepolyamines, polybutylenepolyamines andpolypentylenepolyamines; cf. also Ethylene Amines in Kirk Othmer'sEncyclopedia of Chemical Technology, 2nd Edition, Volume 7, pages 22-37,Interscience Publishers, New York 1965.

[0073] Examples of suitable oligoalcohols and polyols are1,2-butanediol, 2,3-dimethyl-2,3-butanediol, 2,3-hexanediol,1,2-cyclohexanediol, (mono-, di-)-pentaerythritol, 1,7- and2,4-heptanediol, 1,2,3-, 1,2,4-, 1,2,5- and 2,3,4-hexanetriol, 1,2,3-and 1,2,4-butanetriol, 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol,1,10-decanediol, 2-hydroxymethyl-2-methyl-1,3-propanediol,2-hydroxymethyl-2-ethyl-1,3-propanediol, sorbitol, mannitol andinositol. Furthermore, C₅- and C₆-sugars, such as glucose and fructose,are also suitable.

[0074] Examples of (oligo)alkylene glycols are (tri-, tetra-, penta- andhexa)ethylene glycol, tri-, tetra-, penta- and hexa)propylene glycol and(tri-, tetra-, penta- and hexa)butylene glycol.

[0075] Examples of polyalkylene glycols are polytetrahydrofuran,polyethylene glycol and polypropylene glycol. Preferred polyalkyleneglycols are polyethylene glycol and polypropylene glycol. Polyethyleneglycol and polypropylene glycol and their block copolymers which have anumber average molecular weight M_(n) of from 300 to 5 000, preferablyfrom 300 to 2 000, particularly preferably from 500 to 1 500, areparticularly preferably used.

[0076] Such polyethylene glycols are available, for example, under thetrade name Pluriol® E from BASF AG, such as Pluriol® E 300 having anM_(n) of 300, Pluriol® E 600 having an M_(n) of 600, Pluriol® E 4000having an M_(n) of 4 000 and Pluriol® E 5000 having an M_(n) of 5 000.Polyethylene-polypropylene glycol block copolymers are available, forexample, under the trade name Pluronic® PE from BASF AG, such asPluronic® PE 3500 having an M_(n) of 1 900 and an ethylene oxide contentof 50% by weight.

[0077] If the novel compounds and/or the novel mixtures are used inoil-in-water emulsions, stable vesicles can be produced. This can beeffected, for example, by the action of ultrasound. The novel compoundsand/or the novel mixtures can moreover be used in a variety of ways, forexample as additives in fuels and lubricants, as corrosion-inhibitingadditives in water-containing liquids and as dispersants for inorganicand organic solids dispersions. The novel compounds and/or the novelmixtures can furthermore be used as surfactants for washing and cleaningformulations. The high molecular weight compounds of the formula (Ib)which contain a monovalent radical of a polyethylene glycol as ahydrophilic block are particularly suitable for stabilizing inorganicand organic solids dispersions.

[0078] The novel compounds and/or novel mixtures are also suitable asemulsifiers for water-in-oil emulsions in which the oil phase is formedby a vegetable, animal or synthetic oil or fat. Such emulsions are usedin the cosmetics or pharmaceutical sector. Examples of such oils or fatsare triglycerides and glycol esters of lauric acid, myristic acid,stearic acid, palmitic acid, oleic acid, linoleic acid and linolenicacid.

[0079] The novel compounds and/or novel mixtures are particularlyadvantageously used as emulsifiers for water-in-oil emulsions in whichthe oil phase is formed by a fuel or a light or heavy heating oil. Allconventional fuels may be used, for example diesel fuels, gasoline fueland kerosene. Diesel fuel is preferably used.

[0080] In general, purification of the novel compounds and theirintermediates is not necessary; only in certain applications, forexample when these compounds are used as emulsifiers for water-in-oilemulsions in the cosmetics or pharmaceutical sector, purification may benecessary.

[0081] The present invention relates to the use of novel compoundsand/or novel mixtures as emulsifiers in the preparation of water-in-oilemulsions as well as to the water-in-oil emulsions themselves. Novelwater-in-oil emulsions generally contain from 95 to 60% by weight ofoil, from 3 to 35% by weight of water and from 0.2 to 10% by weight ofat least one novel compound and/or one novel mixture.

[0082] Novel water-in-fuel emulsions may also contain one or more C₁- toC₄-alcohols and/or monoethylene glycol, in particular monoethyleneglycol. The amount of C₁-C₄-alcohol and/or monoethylene glycol used isfrom 5 to 50% by weight, based on the amount of water. By adding one ormore C₁-C₄-alcohols and/or monoethylene glycol, for example, thetemperature range in which the emulsion is stable can be extended.

[0083] The novel water-in-fuel emulsions have high stability and goodefficiency during combustion. It is furthermore possible to obtain goodexhaust gas values, the emission of soot and NO_(x) being significantlyreduced, in particular in the case of diesel engines. Substantiallycomplete and residue-free combustion without deposits on the assembliesof the combustion apparatus, for example injection nozzles, pistons,annular grooves, valves and cylinder head, can be achieved.

[0084] The water-in-fuel emulsions according to the invention may alsocontain further components in addition to the abovementionedconstituents. These are, for example, further emulsifiers, such assodium laurylsulfate, quaternary ammonium salts, such as ammoniumnitrate, alkylglycosides, lecithins, polyethylene glycol ethers andesters, sorbitan oleates, stearates and ricinolates, C₁₃ oxo alcoholethoxylates and alkylphenol ethoxylates, and block copolymers ofethylene oxide and propylene oxide, such as the Pluronic® grades fromBASF AG. Sorbitan monooleate, C₁₃ oxo alcohol ethoxylates andalkylphenol ethoxylates, for example, octyl- and nonylphenolethoxylates, are preferably used as further emulsifiers.

[0085] A combination of one or more of the abovementioned furtheremulsifiers together with the novel compounds and/or mixtures thereof ispreferably used for the novel water-in-fuel emulsions.

[0086] If these further emulsifiers are used, they are employed inamounts of from 0.5 to 5, preferably from 1 to 2.5, % by weight, basedon the total composition. The amount of this further emulsifier ischosen so that the total amount of emulsifier does not exceed the statedamount of from 0.2 to 10% by weight for the novel compounds and/ormixtures thereof alone.

[0087] For the preparation of the novel water-in-oil emulsions, thenovel compounds and/or novel mixtures are mixed with the oil, the waterand the further, optionally useful components and are emulsified in amanner known per se. For example, the emulsification can be effected ina rotor mixer or by means of a mixing nozzle or of an ultrasonic probe.Particularly good results were obtained when a mixing nozzle of the typeas disclosed in the Applicant's German application with the applicationnumber 198 56 604 of Dec. 8, 1998, was used. Water-in-oil emulsions forthe cosmetics sector as well as water-in-fuel emulsions can be prepared.

[0088] The novel compounds and/or novel mixtures also have alubricity-improving and corrosion-inhibiting effect in addition to theirsurface-active, interface-active and emulsifying properties. Inaddition, they improve the wear protection behavior of liquids. Thenovel compounds and/or novel mixtures are therefore used as additivesfor lubricants, fuels and water-containing liquids, such as radiatorliquids or drilling and cutting fluids. The present invention alsorelates to this use.

[0089] The novel compounds and/or novel mixtures can be added to thefuels and lubricants directly—together with other components.Alternatively, the novel components and/or novel mixtures can first bemixed with other components to give fuel or lubricant additiveconcentrates. These novel fuel or lubricant additive concentrates can beadded undiluted or in a form diluted with one or more solvents orcarrier oils to the fuels or lubricants. The addition in dilute form ispreferred.

[0090] The fuels, lubricants, fuel additive concentrates and lubricantadditive concentrates and water-containing liquids which contain thenovel compounds and/or novel mixtures are likewise a subject of thepresent invention and are to be explained in more detail below.

[0091] Novel fuels generally contain—in addition to conventionalcomponents—at least one novel compound and/or one novel mixture in anamount of from 10 to 5 000, preferably from 20 to 2 000, ppm, based onthe total amount.

[0092] Novel lubricants generally contain from 90 to 99.9, preferablyfrom 95 to 99.5, % by weight of a liquid, semisolid or solid lubricantand from 0.1 to 10, preferably from 0.5 to 5, % by weight of at leastone novel compound and/or one novel mixture, based on the total amount.

[0093] Novel fuel additive and lubricant additive concentratescontain—in addition to conventional components—at least one novelcompound and/or one novel mixture in amounts of from 0.1 to 80, inparticular from 0.5 to 60, % by weight, based on the total weight of theconcentrate.

[0094] Conventional components for fuels or fuel additive concentratesare, for example, additives having a detergent action, as described inthe Applicant's German application with the application number 100 36956.1 of Jul. 28, 2000 (page 14 et seq.), in the Applicant's Germanapplication with the application number 100 03 105.6 of Jan. 25, 2000and in the Applicant's PCT application with the application numberPCT/EP/01/00496. The additives stated there and further fuel additivesdescribed there and having polar groups form part of the presentapplication and are hereby incorporated by reference.

[0095] The novel fuels and fuel additive concentrates may also containfuel additives as described, for example, in European Patentapplications EP-A 0 277 345, 0 356 725, 0 476 485, 0 484 736, 0 539 821,0 543 225, 0 548 617, 0 561 214, 0 567 810, 0 568 873, the German Patentapplications DE-A 39 42 860, 43 09 074, 43 09 271, 43 13 088, 44 12 489,44 25 834, 195 25 938, 196 06 845, 196 06 846, 196 15 404, 196 06 844,196 16 569, 196 18 270, 196 14 349 and WO-A 96/03479.

[0096] Further conventional components are, for example, othercorrosion-inhibiting additives, antioxidants, stabilizers, antistaticagents, organometallic compounds, antiwear additives, markers, cetanenumber improvers, flow improvers and biocides, such as glutaraldehyde orglyoxal. The biocides are usually used in an amount of from 0.01 to 3%by weight, based on the total weight of the concentrate.

[0097] Examples of further corrosion-inhibiting additives are thosebased on ammonium salts of organic carboxylic acids, which salts tend toform films, or on heterocyclic aromatics in the case of corrosionprotection of nonferrous metals.

[0098] Examples of stabilizers are those based on amines, such asp-phenylenediamine, dicyclohexylamine or derivatives thereof, or onphenols, such as 2,4-di-tert-butylphenol or3,5-di-tert-butyl-4-hydroxyphenylpropionic acid.

[0099] Examples of organometallic compounds are ferrocene andmethylcyclopenta-dienyl-manganese tricarbonyl.

[0100] Examples of cetane number improvers are organic C₂-C₁₀-nitrates,such as 2-ethylhexyl nitrate, and inorganic cetane number improvers forthe aqueous phase, such as ammonium nitrate. 2-Ethylhexyl nitrate andammonium nitrate are preferably used. The cetane number improvers areusually used in an amount of from 0.05 to 5% by weight, based on thetotal weight of the concentrate.

[0101] Suitable solvents for the novel fuel and lubricant additiveconcentrates are aliphatic and aromatic hydrocarbons, such as solventnaphtha, isododecane, mihagol (an industrial mixture ofC₁₀-C₁₂-paraffins), the fuels and lubricants themselves and carrieroils.

[0102] Carrier oils which likewise serve for diluting the fuel andlubricant additive concentrates are, for example, mineral carrier oils(base oils), in particular those of viscosity grade Solvent Neutral (SN)100 to 500, and synthetic carrier oils based on polyolefins,(poly)esters, (alkylphenol-initiated) polyethers, (aliphatic)(alkyl-phenol-initiated) polyetheramines, and carrier oils based onalkoxylated long-chain alcohols or phenols. Examples of particularlysuitable synthetic carrier oils are those based on polyolefins,preferably based on polyisobutylene and on poly-α-olefins, having anumber average molecular weight M_(n) of from 400 to 1 800. Polyethyleneoxides, polypropylene oxides, polybutene oxides and mixtures thereof arealso suitable carrier oils. Further suitable carrier oils and carrieroil mixtures are described, for example, in DE-A 38 38 918, DE-A 38 26608, DE-A 41 42 241, DE-A 43 09 074, U.S. Pat. No. 4,877,416 and EP-A 0452 328.

[0103] Novel water-containing liquids contain the novel compounds and/ornovel mixtures, if required in combination with further conventionalcorrosion-inhibiting additives, in general in an amount of from about 1to 10% by weight, based on the total amount.

[0104] The examples which follow illustrate the invention.

EXAMPLES Example 1 Preparation of the Compounds of the Formulae (Ia) and(Ib)

[0105] The composition of the compounds prepared is shown in table 1.

[0106] The polyisobutylene used was Glissopal® from BASF AG, having anumber average molecular weight M_(n) of from 380 to 8 400, a content ofvinylidene terminal groups of >70 mol %, a polydispersity M_(w)/M_(n) offrom 1.15 to 1.8 and a polymer skeleton structure comprising more than85% of isobutylene units. This polyisobutylene serves as a startingmaterial for the synthesis of succinic anhydride substituted by apolyisobutylenyl group (PIBSA=polyisobutylene succinic anhydride).

[0107] The polyethylene glycol used was Pluriol® E from BASF AG, havinga number average molecular weight M_(n) of from 300 to 5 000. Thepolyethylene glycoIpolypropylene glycol block copolymer used wasPluronic® PE 3500 from BASF AG, having a number average molecular weightM_(n) of 1 900 and an ethylene oxide content of 50% by weight.

[0108] The solvents used were heptane, mihagol, a mixture ofC₁₀-C₁₂-paraffins from Wintershall, and Solvesso® 150, a mixture ofaromatic hydrocarbons, from ExxonMobil Chemical.

[0109] The ion exchanger used was the ion echanger commerciallyavailable under the name Ambossol® from Clariant.

[0110] The maleation of the polyisobutylenes to give the correspondingsuccinic anhydrides was carried out by methods known per se and isdescribed, for example, in DE-A 195 19 042, DE-A 43 19 671 and DE-A 4319 672.

[0111] The compounds obtained were characterized by the acid number, theOH number, the viscosity and/or the IR spectra. The OH number wasdetermined using high-boiling solvents with correction for the solvent,i.e. the OH number of the compounds in the respective solvent wasmeasured and then extrapolated to the pure substance. In the case oflow-boiling solvents, such as heptane, the solvent was removed bydistillation and the OH number of the pure substance was determined.

[0112] The viscosities were determined according to DIN 51562. TABLE 1Composition of the compounds of the formula (Ia) or (Ib) Hydrolysis Com-Glissopal ® number pound M_(n) M_(w)/M_(n) of PIBSA Polar reactant A 5501.23 148 (HO—CH₂—CH₂—)₂NH B 550 1.23 148 (HO—CH₂)₃—CNH₂ C 750 1.31 120D-sorbitol D 380 1.15 210 Pluriol ®E 300 E 550 1.23 147 Pluriol ®E 300and (HO—CH₂—CH₂—)₂NH F 1000 1.31 95 Pluriol ®E 600 G 2300 1.52 40Pluriol ®E 1500 H 5200 1.38 18.3 Pluriol ®E 4000 I 8400 1.45 12.0Pluriol ®E 5000 J 1000 1.31 95 (HO—CH₂—CH₂—)₂NH K 1000 1.31 95Pluronic ® PE 3500 L 550 1.31 148 Choline M 1000 1.31 95 Monoethyleneglycol 2300 1.52 40

[0113] Preparation of the Compound A:

[0114] A 1 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 250 g of PIBSA 550 and heated to 90° C. 67 gof diethanolamine are metered via the dropping funnel in the course of 5minutes. The mixture is heated gradually to 130° C. or 170° C. After 2hours at 170° C., the brown reaction product is filtered at 100° C.

[0115] Preparation of the Compound B:

[0116] A 2 l four-necked flask with a stirrer, distillation bridge andthermocouple is filled with 525 g of PIBSA 550, 650 g of Solvesso® 150and 175 g of trihydroxymethylaminomethane (TRIS). The mixture is heatedgradually to 130° C. or 170° C. Water liberated is removed by means of anitrogen stream; the reaction time is 3 hours. The OH number wasdetermined as 250 with correction for solvent.

[0117] Preparation of the compound C:

[0118] A 1 l four-necked flask with a stirrer, distillation bridge andthermocouple is filled with 310 g of PIBSA 750 and 60 g of D-sorbitol.The mixture is gradually heated to 160° C. or 220° C. Water liberated isremoved by means of the nitrogen stream; after 3 hours at 220° C.,dilution is effected with 200 g of mihagol and filtration is carried outwhile hot. A yellow, viscous product solution (65%) is obtained.

[0119] Preparation of the Compound D:

[0120] A 2 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 350 g of Pluriol® E 300 and is degassed at90° C. in the course of 30 minutes under reduced pressure. A solution of650 g of PIBSA 380 in 350 g of heptane is metered via a dropping funnelat 80° C. in the course of 5 minutes. The mixture is gradually heated to110° C. or 140° C. Heptane is distilled off at reduced pressure (350mbar) during this procedure. After 3 hours at 140° C., a yellow producthaving a viscosity of 105 mm²/s (100° C.) is obtained; OH number: 70;acid number: 73; IR: intense band at 1 735 cm⁻¹ (ester).

[0121] Preparation of the Compound E:

[0122] A 2 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 300 g of Pluriol® E 300 and is degassed at90° C. in the course of 30 minutes under reduced pressure. A solution of750 g of PIBSA 550 in 450 g of heptane is metered via a dropping funnelat 80° C. in the course of 5 minutes. The mixture is gradually heated to110° C. or 140° C. . Heptane is distilled off at reduced pressure (350mbar) during this procedure. After 3 hours at 140° C., 105 g ofdiethanolamine are added a little at a time at 95° C. After a further 20minutes at 95° C., the orange-brown product is filtered while hot. OHnumber: 55; IR: intense band at 1 736 cm⁻¹ (ester).

[0123] Preparation of the Compound F:

[0124] A 2 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 400 g of Pluriol® E 600 and is degassed at90° C. in the course of 30 minutes under reduced pressure. A solution of790 g of PIBSA 1000 in 450 g of heptane is metered via a dropping funnelat 80° C. in the course of 5 minutes. The mixture is gradually heated to110° C. or 140° C. Heptane is distilled off under reduced pressure (350mbar) during this procedure. After 3 hours at 140° C., a yellow producthaving a viscosity of 1650 mm²/s (100° C.) is obtained. OH number: 43;acid number: 40; IR: intense band at 1 734 cm⁻¹ (ester).

[0125] Preparation of the Compound G:

[0126] A 1 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 150 g of Pluriol® E 1500 and is degassed at90° C. in the course of 30 minutes under reduced pressure. A solution of280 g of PIBSA 2300 in 300 g of mihagol is metered via a dropping funnelat 80° C. in the course of 5 minutes. The mixture is gradually heated to110° C. or 140° C. After 3 hours at 140° C., a yellow, highly viscousproduct solution is obtained. Viscosity 1750 mm²/s, 100° C.; OH number:9; acid number: 8.1; IR: band at 1 736 cm⁻¹.

[0127] Preparation of the Compound H:

[0128] A 1 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 150 g of Pluriol® E 4000 and is degassed at90° C. in the course of 30 minutes under reduced pressure. A solution of250 g of PIBSA 5200 in 300 g of mihagol is metered via a dropping funnelat 80° C. in the course of 5 minutes. The mixture is gradually heated to110° C. or 140° C. After 3 hours at 140° C., a beige wax is obtained. OHnumber: 4.3; acid number: 3.5; IR: band at 1 736 cm⁻¹ (ester).

[0129] Preparation of the Compound I:

[0130] The synthesis is effected analogously to the synthesis of thecompound H from PIBSA (basis: reactive PIB 8400; M_(w)/M_(n)=1.45) andPluriol® E 5000. The product is isolated as cream-colored wax (60%strength in mihagol); IR: 1 737 cm⁻¹.

[0131] Preparation of the Compound J for Comparative Example 1:

[0132] The synthesis is effected analogously to the synthesis of thecompound A from PIBSA 1000 (basis: reactive PIB 1000; M_(w)/M_(n)=1.31)and diethanolamine (cf also U.S. Pat. No. 4,708,753). The product isisolated as a brown, highly viscous liquid and has a lower hydrophiliccontent A-R than compound A.

[0133] Preparation of the Compound K:

[0134] The synthesis is effected analogously to the synthesis of thecompound F from PIBSA 1000 (basis: reactive PIB 1000; M_(w)/M_(n)=1.31)and Pluronic® PE 3500. The product is isolated as an orange-yellow,highly viscous liquid. Viscosity: 2 100 mm²/s; 100° C.

[0135] Preparation of the Compound L:

[0136] A 1 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 75 g of a 45% strength methanolic solutionof choline from Fluka and 150 g of mihagol. Methanol is then removed at50° C. and reduced pressure (50 mbar) (45 minutes). 200 g of PIBSA 550is metered into this suspension and the mixture is heated to 90° C. inthe course of 15 minutes. After 60 minutes, the temperature is increasedto 170° C. and stirring is carried out for a further two hours. Thebrown reaction product is filtered at 100° C.

[0137] Preparation of the Compound M for Comparative Example 2:

[0138] A 1 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 300 g of PIBSA 2300, 200 g of PIBSA 1000 and200 g of mihagol and is heated to 95° C. At 95° C., 17.2 g of ethyleneglycol are metered. The mixture is heated to 130° C. and is stirred atthis temperature for three hours. The brown reaction product is filteredat 100° C.

[0139] The emulsifier of comparative example 2 was prepared according tothe principle of WO 00/15740, example C-1, page 34.

[0140] Preparation of the Compound N for Comparative Example 3:

[0141] (The preparation was carried out analogously to compound F.However, compound F has a A-R content of 35.3% whereas the hydrophilicmoiety A-R accounts for 15.4% in compound N.)

[0142] A 2 l four-necked flask with a stirrer, dropping funnel andthermocouple is filled with 100 g of Pluriol® E 200 and is degassed at90° C. in the course of 30 minutes under reduced pressure. A solution of590 g of PIBSA 1000 in 450 g of heptane is metered via a dropping funnelat 80° C. in the course of 5 minutes. The mixture is gradually heated to110° C. or 140° C. Heptane is distilled off under reduced pressure (350mbar) during this procedure. After 3 hours at 140° C., an amber-coloredproduct having a viscosity of 1 450 mm²/s (100° C.) is obtained.

Example 2 Preparation of the Water-in-Fuel Emulsions

[0143] The preparation or the composition of the fuel mixtures is listedin table 2.

[0144] The hydrophilic or water-soluble components were dissolvedbeforehand in the aqueous phase, and lipophilic components in the dieseloil. 500 g of this mixture were homogenized with 100 ml of water in thecourse of 15 minutes at a speed of 2 400 rpm using an Ultra-Turrax®(Jahnke and Kunkel laboratory apparatus T25). The preparation of theemulsion on the industrial scale and the engine tests were carried outanalogously to DE-A 198 56 604 of the Applicant (filed on Dec. 8, 1998),using a mixing nozzle described there. The pressure in the mixingapparatus was from 50 to 200, preferably 120, bar (before the orifice)at a total conversion of 12 kg/h. TABLE 2 Composition of the emulsionsExample Compound Com- Com- Com- [% by parison parison parison weight) 12 3 4 5 6 7 1 2 3 A 1.4 — — — 1.5 — — — — — B — — — — — — — — — — C₁₃oxo 0.2 0.2 — — — 0.2 0.3 0.3 0.3 0.3 alcohol ethoxylate having 5[—CH₂—CH₂—O] units Alkylphenol 0.2 — 0.2 0.3 0.3 — — — — — ethoxylate C— — — 1.3 — —— — — — — D — — 1.5 — — — 0.5 — — — E — — — — — 1.8 — — — —F — 0.3 — — — — — — — — G — — 0.2 — 0.3 — — — — — H — — — — — — — — — —I — — — 0.4 — — — — — — J — — — — — — — 1.8 — — K — — — — — — 1.0 — — —L — 1.6 — — — — — — — — M — — — — — — — — 1.7 — N — — — — — — — — — 1.7Diesel 76.3 76.0 76.1 76.2 76.0 76.5 76.2 76.0 76.1 76.1 (EN 590) Water20 20 20 15 20 15 20 15 15 15 Methanol — — — 2 — 3 — — — — Ethylene — —— 3 — 2 — 5 5 5 glycol Biocide* 0.4 0.4 0.5 0.3 0.4 — 0.5 0.4 0.4 0.4NH₄NO₃ 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5

Example 3 Investigations into the Stability of the Water-in-FuelEmulsions

[0145] The size of the water drops was determined physically by laserdiffraction (×3,2 values) using a Malvern Mastersizer 2000 from MalvernInstruments GmbH. The method of measurement is described, for example,in Terence Allen, Particle Size Measurement, Volume 1, 5_(th) Edition,Kluwer Academic Publishers, Dordrecht, Netherlands 1999. Depending onthe size distribution actually present, further methods, e.g. dynamiclight scattering, single particle count and ultrasound extinction, aresuitable in addition to laser light diffraction.

[0146] The size of the water drops is a measure of the quality of theemulsion. The smaller the drop size, the better or more stable is theemulsion. The corresponding values for the drop size (×3,2 values) arelisted in table 3. Table 3 shows that, with the use of the novelcompounds as well as the novel mixtures, some of the emulsions havesubstantially smaller drop sizes than the comparative emulsions. Thatthe drop size is actually a measure of the stability of the emulsion atroom temperature is evident from the stability values determined bystorage experiments. The emulsions having larger drop sizes also have apoorer shelf life. TABLE 3 Drop size and stability of the water-in-fuelemulsions Com- Com- Com- parison parison parison Example 1 2 3 4 5 6 7 12 3 Drop size 2.9 2.2 1.0 3.1 2.5 3.2 2.7 5.4 6.2 6.8 (X 3,2 value) [μm]Storage test (room 86 >95 >95 91 89 79 77 61 58 49 temperature)* [%emulsion] Storage test 91 100 100 89 93 80 82 73 75 69 (70° C.)** [%emulsion] Storage test — 65 — 91 95 89 — 62 64 63 (−20° C.)** [%emulsion]

[0147] The stability of the emulsions was checked in a static storagetest at 20° C. (for 12 weeks) and additionally with varying temperatures(−20° C. and 70° C., for 1 week each). For this purpose, the emulsionwas introduced into a graduated 100 ml upright cylinder and its qualitywas assessed visually under said conditions.

[0148] Compared with the use of emulsifiers from the prior art(comparative examples), an improvement in the shelf life which issignificant in some cases is to be observed with the use of the novelemulsifiers and mixtures thereof. The evaluation of the storageexperiments at −20° C. was subsequently carried out at room temperature.The emulsion according to example 2 is comparatively homogeneous afterthawing, even without the addition of an antifreeze (e.g. monoethyleneglycol). Otherwise, phase separation, i.e. breaking of the emulsion,occurred after or even during warming up.

[0149] A comparison of the quality of the novel emulsions with that ofan emulsion according to WO 00/15740 (example C-1, page 34, comparativeexample 2) proves that a combination of a low molecular weight componentand a higher molecular weight component to give a correspondinglybridged compound leads to a significantly poorer emulsifier than a novelmixture of the isolated compounds.

Example 4 Use of the Novel Compounds of the Formula (I) as Antirust andAntiwear Additives

[0150] An iron sheet measuring 20×40 mm is blasted with 40 μm glassbeads and then immersed—similarly to ASTM D-665—in the emulsionsprepared under example 2 and stored at 40±1° C. for 24 hours. After 24hours, the iron sheet is investigated with regard to rust formation.Here:

[0151] ++ means no rust formation;

[0152] +0 means slight rust deposit;

[0153] −0 means rust formation over more than 25% of the area of thetest sheet;

[0154] −− means rust formation over more than 50% of the test sheet.

[0155] As shown by the results in table 4, in some cases only a slightrust deposit was observed with the use of the novel compounds ascorrosion-inhibiting additives. In contrast, rust formation occurred onmore than 50% of the area of the test sheet when C₁₃ oxo alcoholethoxylate was used.

Example 5 Use of the Novel Compounds of the Formula (I) in Fuels andtheir Antiwear Behavior

[0156] In each case the compounds shown in the table were dissolved in adiesel fuel without additives (Miro, Karlsruhe). The concentration ofadditive in the diesel fuel was 75 ppm. The antiwear behavior wasassessed by the HFRR test (high frequency roller rig test), which wascarried out according to ISO 12156-1. The length of the resultingfurrows was measured and was used as a measure of the wear. The shorterthe furrows, the better was the wear protection of the additiveintroduced. Diesel fuel without additives was used for comparison. Asshown in table 4, the novel compounds provided protection from wear.TABLE 4 Length of the furrows Additive [μm] Corrosion Compound B 380 +0Compound C 490 −0 Compound D 315 +0 Compound E 295 ++ Compound F 320 ++Compound G 420 +0 Compound J 495 −0 No additive 605 − −

We claim:
 1. A compound of the formula (Ia) or (Ib)

where L^(a) is a polyisobutylenyl group having a number averagemolecular weight M_(n) of from 300 to 1 000, L is a polyisobutylenylgroup having a number average molecular weight M_(n) of from 2 000 to 20000, -A- is —O—, —N(H)— or —N(R¹)—, M⁺ is H⁺ or an alkali metal ion, 0.5alkaline earth metal ion or NH₄ ⁺, where one or more H in NH₄ ⁺ may bereplaced by alkyl, R is a linear or branched saturated hydrocarbonradical which carries at least one substituent selected from the groupconsisting of OH, NH₂ and NH₃ ⁺ and, if required, one or more C(O)Hgroups and, if required, contains one or more nonneighboring —O— and/orsecondary amines and/or tertiary amines, where one or more H in the NH₂—or NH₃ ⁺ groups may be replaced by alkyl, and R¹ is a linear or branchedsaturated hydrocarbon radical which, if required, carries one or moresubstituents selected from the group consisting of OH, NH₂, NH₃ ⁺ andC(O)H and, if required, contains one or more nonneighboring —O— and/orsecondary amines and/or tertiary amines, and where one or more H in theNH₂— or NH₃ ⁺ groups may be replaced by alkyl, and the proportion of A-Rin the compound of the formula (Ia) or (Ib) is at least 20% by weight.2. The compound as claimed in claim 1, wherein L^(a) is apolyisobutylenyl group having a number average molecular weight M_(n) offrom 350 to 950, in particular from 350 to 650, and L^(b) is apolyisobutylenyl group having a number average molecular weight of from2 000 to 12 000, in particular from 2 300 to 5
 000. 3. The compound asclaimed in claim 1 or 2, wherein L^(a) and L^(b) are each apolyisobutylenyl group which has a polydispersity of ≦3.0, preferablyfrom 1.1 to 2.5, particularly preferably from 1.1 to 2.0.
 4. Thecompound as claimed in any of claims 1 to 3, wherein L^(a) and L^(b) areeach a polyisobutylenyl group which is composed of at least 80% byweight of isobutylene units.
 5. The compound as claimed in any of claims1 to 4, wherein the proportion of A-R in the compound of the formula(Ia) or (Ib) is at least 25, in particular from 35 to 60, % by weight.6. The compound as claimed in any of claims 1 to 5, wherein A is —O— andR is a monovalent radical of an oligomer or polymer of ethylene oxideand/or propylene oxide or a monovalent radical of a block copolymer ofethylene oxide and propylene oxide.
 7. A mixture containing (a) not morethan 99, preferably from 98 to 80, particularly preferably from 97 to85, % by weight of at least one compound of the formula (Ia),

(b) at least 1, preferably from 2 to 20, particularly preferably from 3to 15, % by weight of at least one compound of the formula (Ib), whereL^(a) is a polyisobutylenyl group having a number average molecularweight M_(n) of from 300 to 1 000 and L^(b) is a polyisobutylenyl grouphaving a number average molecular weight M_(n) of from 2 000 to 20 00,-A- is —O—, —N(H)— or —N(R¹)—, M⁺ is H⁺ or an alkali metal ion, 0.5alkaline earth metal ion or NH₄ ⁺, where one or more H in NH₄ ⁺ may bereplaced by alkyl, R is a linear or branched saturated hydrocarbonradical which carries at least one substituent selected from the groupconsisting of OH, NH₂ and NH₃ ⁺ and, if required, one or more C(O)Hgroups and, if required, contains one or more nonneighboring —O—— and/orsecondary amines and/or tertiary amines, where one or more H in the NH₂—or NH₃ ⁺ groups may be replaced by alkyl, and R¹ is a linear or branchedsaturated hydrocarbon radical which, if required, carries one or moresubstituents selected from the group consisting of OH, NH₂, NH₃ ⁺ andC(O)H and, if required, contains one or more nonneighboring —O— and/orsecondary amines and/or tertiary amines, and where one or more H in theNH₂— or NH₃ ⁺ groups may be replaced by alkyl, and the proportion of A-Rin the compound of the formula (Ia) is at least 10% by weight and thatin the compound of the formula (Ib) is at least 20% by weight.
 8. Amixture as claimed in claim 7, wherein the proportion of A-R in thecompound of the formula (Ia) is at least 15, preferably at least 20,particularly preferably at least 25, very particularly preferably from35 to 60, % by weight and/or that in the compound of the formula (Ib) isat least 25, in particular from 35 to 60, % by weight.
 9. The mixture asclaimed in claim 7 or 8, wherein L^(a) and/or L^(b) are each apolyisobutylenyl group which is composed of at least 80% by weight ofisobutylene units.
 10. A process for the preparation of compounds of theformula (Ia) and (Ib) as claimed in any of claims 1 to 6, in whichpolyisobutylene is reacted with fumaryl dichloride, fumaric acid, maleyldichloride, maleic acid or maleic anhydride, the reaction productobtained is reacted with ethylene oxide, propylene oxide, alkanolamines,polyamines, oligoalcohols, polyols, oligoalkylene glycols, polyalkyleneglycols, carbohydrates or sugars and the free carboxyl group present is,if required, converted with NH₃, an amine or an alkali metal salt oralkaline earth metal salt into the corresponding salt.
 11. The use of acompound of the formula (Ia) and/or (Ib) as claimed in any of claims 1to 6 and/or of a mixture as claimed in any of claims 7 to 9 as asurface-active substance, as an emulsifier, as an antiwear additive, asa lubricity additive or as a corrosion-inhibiting additive in fuels,lubricants or fuel additive and lubricant additive concentrates or as acorrosion-inhibiting additive in water-containing liquids.
 12. The useas claimed in claim 11, the compound and/or the mixture being used as anemulsifier in the preparation of water-in-oil emulsions, in particularof water-in-fuel emulsions, or as a surfactant for industrial andcosmetic washing and cleaning formulations.
 13. A fuel, lubricant, fueladditive concentrate, lubricant additive concentrate or water-containingliquid containing one or more compounds of the formula (Ia) and/or (Ib)as claimed in any of claims 1 to 6 and/or a mixture as claimed in any ofclaims 7 to 9, preferably a water-in-fuel emulsion containing from 60 to95% by weight of fuel, preferably diesel fuel, from 3 to 35% by weightof water and from 0.2 to 10, preferably from 0.5 to 5, % by weight ofone or more compounds of the formula (Ia) and/or (Ib) as claimed in anyof claims 1 to 6 and/or of a mixture as claimed in any of claims 7 to 9as an emulsifier.
 14. A washing or cleaning formulation containing oneor more compounds of the formula (Ia) and/or (Ib) as claimed in any ofclaims 1 to 6 and/or a mixture as claimed in any of claims 7 to
 9. 15.The emulsion as claimed in claim 13, wherein, in addition to one or morecompounds of the formula (Ia) and/or (Ib), one or more furtheremulsifiers, preferably sorbitan monooleate, C₁₃ oxo alcohol ethoxylatesor alkylphenol ethoxylates, and/or one or more biocides, preferablyNH₄NO₃ and/or glyoxal, particularly preferably glyoxal, are present. 16.A process for the preparation of an emulsion as claimed in claim 13 or15, wherein the respective components are mixed with one another and areemulsified in a manner known per se, preferably in a mixing nozzle.